Figure 2.

(A) [¹¹C]Raclopride binding potential (BP_ND) for each group and drink order. Each group (family history–positive [FHP], family history–negative [FHN], alcohol use disorder [AUD]) is represented by four bars: the placebo day (Pl) and the alcohol day (Alc) for each order (alcohol beverage at first scan [AP]; alcohol beverage at second scan [PA]). In all three groups, alcohol (second bar in each pair) resulted in greater dopamine release (reduction in BP_ND) than placebo did. However, the FHP participants showed much smaller alcohol-induced reduction in BP_ND when placebo was first (FHP-PA) than when placebo was second (FHP-AP). In contrast, the FHN and AUD participants showed moderate BP_ND reductions between placebo and alcohol day that were similar regardless of drink order. The six within-group differences between the placebo and alcohol day for each order (as percent of placebo) are the six data points in Figure 1. Bar heights indicate group mean BP_ND and error bars indicate SD (data shown in Table 3). (B) [¹¹C]Raclopride BP_ND for each group and drink order, voxelwise maps. These images display the BP_ND values shown as regional means in panel (A). Note that the greatest intensity changes from placebo to alcohol scan occur for the FHP-AP group, and the smallest changes occur for the FHP-PA group. MRI, magnetic resonance imaging; VST, ventral striatum.